Resting angle of a leaning beam; gear trains for contrary motions
A beam on a cord seeks its support; pinions turning the same or opposite ways
One study asks at what degree of obliquity the beam a n will come to rest: since its support m c carries the whole beam and nothing holds the far end at n, the beam must fall until its head n meets b, or until the beam's centre drops below the centre of its support, between c and d. The rest of the folio is filled with gear and belt trains: turning the wheel f makes the pinions n m revolve in opposite directions, while other rows show six movables all turning the same way, two little wheels turning together, and six wheels in mutually contrary motion. Small corner diagrams keyed c b and a m n set out the beam problem.
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At what angle the leaning beam stops
It is asked at what degree of obliquity the beam a n will come to rest. Since m c sustains the whole beam and nothing holds the opposite end of the cord at n, the beam of necessity falls until its head n joins with b, or until the beam's centre drops below the centre of its support, as between c and d.
Gear trains: same and contrary motions
Turning the wheel f makes the pinions n m turn in contrary motions to one another, a way to produce two opposite motions at once. Other rows show six movables all turning the same way, two little wheels turning together, and a train of six wheels each contrary to its neighbour.
